I was looking from some experienced input as to a larger fin for my Rio M. I've seen some recommendations as to a True Ames Shallow Weed or a Sweeper. Being new (after almost 20 years out of windsurfing) a few thing have changed and for the better. I'm 95k and have a 7.5, 8.5 and 9.5. I suspect going from the stock Darke Shallow 410 to a little longer fin will help in plainning.